EP1224346B1 - Textile material in sheet form for technical uses - Google Patents

Abstract

A textile material in sheet form consisting of a warp and weft fabric produced by rovings of continuous technical filaments (for example, glass, carbon, or aramide filaments) without torsion is disclosed. The textile material may be produced according to a plain weave or derivative thereof, for example, the density of the warp threads (C) and the weft threads (T) may be balanced. The warp threads(C) or weft threads (T) are weakened or cut individually at predetermined intervals without any noticeable deterioration in the characteristics of the weft or warp threads located beneath the weakened or cut area. The areas in which a series of threads of the fabric (C) or (T) are weakened or cut may be produced with a lateral and vertical thread course between two consecutive threads.

Description

Technical area

The present invention relates to a new type of textile textile material usable for technical uses, such as reinforcement structures composite materials, laminate complexes, complexes for producing waterproofing in the building sector, or in complex public works intended for the repair of pipes and, more generally, for all types of structure comprising a resin-based, polyester or other matrix, reinforced by a reinforcing textile sheet.

Previous techniques

The use of textile tablecloths, in particular based on glass fibers, has been proposed for decades, to carry out the reinforcement of plastic material when manufacturing laminate or molded structures, flat or shaped, as well that this appears in particular from the patents FR-A-1 469 065, FR-A-1 394 271, US-A-3 930 091, FR-A-2 034 787 and FR-A-2 568 275.

Such textile structures have also been proposed with a view to being used in the field of building and public works for the realization of waterproof screeds, in particular in reinforced bitumen (FR 2 409 338) for making complexes usable for the repair of pipes or similar works, buried or not (EP-A-542,639).

It appears from all these documents that the reinforcement structure must be adapted depending on the various applications.

The basic structures proposed for decades to achieve such reinforcements, in particular from the appearance of the glass strands, are on the one hand, the mats which consist of staple fibers and are in the form of a structure similar to a "felt", and on the other hand, the warp and weft fabrics made up of threads or roving ribbons based on glass filaments with continuous filaments.

In addition to these types of structures, tablecloths have also been proposed. "Unidirectional" in which the glass strands are arranged in a same longitudinal direction, these wires being linked to each other either chemically (French patent 1,394,271), or by means of a seam (French patent 1,469 065).

It has also been proposed in US Pat. No. 3,930,091 to produce a sheet, which unlike the previous ones, consists mainly of glass fibers extending transversely to the length of said ply, these wires being linked together by a loose tying chain, consisting of threads coated with a hot-melt or similar material, allowing, after heat treatment in particular, to maintain the weft threads parallel to each other.

Compared to balanced warp and weft fabrics, such plies unidirectional do not allow to realize reinforced articles to both longitudinally and transversely.

Furthermore, for many applications, there is the problem of having a reinforcement structure which can deform during its implementation, especially when making shaped molded articles.

In the case of a reinforcement in the form of a sheet unidirectional, it is possible to obtain such “deformability” in the transverse direction relative to the orientation of the wires, for example using as binder threads for elastic threads.

In the case of a balanced warp and weft fabric, it can be considered to obtain a possibility of deformation by selecting the weaving weave.

Indeed, it is well known that certain weaves of the satin, twill, lead to deformable woven structures. However, the possibilities of deformation are limited to a few percent.

Such a problem of possibility of deformability of the reinforcement is found also within the framework of the use of complex structures, constituted by a combination of a nonwoven mat and bidirectional woven structures or unidirectional, which are used in particular for repairing pipes according to a technique which consists in covering the internal surface of the structure to renovate with a tubular structure made from a complex material flexible, comprising a membrane impermeable to fluids and a structure of fibrous base which is impregnated with a non-polymerized synthetic resin and, after plating said complex against the surface of the structure to be repaired, causing the polymerization of the resin so as to form an internal "sleeving".

Regarding the establishment of such a tubular structure inside the led to renovate, two main techniques are used today.

The first, which emerges more particularly from British patent 1,357 355, consists in introducing the tubular material previously produced inside of the pipe to be renovated, so that the fibrous structure is positioned in look at the surface to be renovated and that the impermeable surface layer is, as for it, located inside opposite the flow zone.

After installation over the entire length of the pipe, the sheath is put under pressure, so that it comes to press against the internal surface. We then causes polymerization of the resin.

Another technique, called "flipping", consists, as well as that spring of the British patent 1 449 455, to introduce the sheath previously formed with the waterproof surface located on the outside, then, when introduced inside of the pipe, to cause the reversal of said sheath, so that the fibrous structure comes into contact with the inner surface of the tube and that the layer waterproof is located inside.

Such a procedure allows the fiber structure to be impregnated with uncured resin as it is placed inside the conduct.

Furthermore, the polymerization can also be carried out continuously, by example by light radiation.

These two techniques, and more particularly the implementation technique by inversion, implies having a basic material which has sufficient mechanical characteristics in the lengthwise direction to ensure the implementation.

Furthermore, it is desirable that the tubular structure can also present possibilities of deformation under the action of stresses exerted in the transverse direction to allow the sheath to press perfectly against the wall surface to be renovated when the structure is pressurized, in order to that it perfectly matches the surface of the structure to be renovated.

Consequently, in all uses using reinforcements textiles in the form of tablecloths, can pose the problem of having a possibility deformation both in the long direction and in the cross direction while retaining, .in the final product (laminate, molded, waterproofing, complex for repairing pipes), high mechanical characteristics in all directions.

Statement of the invention

Now we have found, and this is what is the subject of the present invention, a new type of fabric that can be used either alone or in combination with others structures, such as non-woven fibrous webs, reinforcement grids, etc., so to constitute a complex which not only makes it possible, during its implementation, to maintain good mechanical properties, in particular resistance to traction, both in warp and weft direction, while allowing deformation in the other direction, and ensuring characteristics in the final product mechanical equivalent to those imparted by a non-deformable fabric.

The invention also relates to a method and an installation for production of such a type of fabric and the use of the latter to produce complexes such as waterproofing coatings, structures for repairing pipes.

• le tissu est réalisé selon une armure unie ou dérivée de l'uni, la densité en chaíne et en trame étant de préférence équilibrée ;
• les fils de chaíne ou de trame sont fragilisés ou coupés individuellement à intervalles prédéterminés sans détérioration notable des caractéristiques des fils de trame ou de chaíne situés en dessous de la zone de fragilisation ou de coupe;
• les zones de fragilisation ou de découpe d'une série de fils du tissu sont réalisées avec un décochement latéral et vertical entre deux fils ou groupes de fils consécutifs.

In general, the material according to the invention consists of a warp and weft fabric made from twist-free wicks of continuous filaments for technical use (glass, carbon, aramid, etc.), wicks which, in the following of the description, will be designated by the generic term "son". Such a fabric is characterized in that:

• the fabric is made in a plain weave or derived from the plain, the warp and weft density is preferably balanced;
• the warp or weft threads are weakened or cut individually at predetermined intervals without significant deterioration in the characteristics of the weft or warp threads located below the weakening or cutting zone;
• the weakening or cutting zones of a series of threads of the fabric are produced with a lateral and vertical detachment between two threads or groups of consecutive threads.

In the present description, by “two consecutive sons or groups of sons”, it is understood that the embrittlement or cutting carried out is actually between two wires with offset of a neighboring wire, possibly by groups of wires, for example simultaneously on the neighboring wire, this offset being produced between two groups consecutive.

In the fabric according to the invention, the strands of filaments constituting the warp and weft threads are in the form of flattened ribbons, of large width relative to the thickness, width advantageously between 3 mm and 15 mm and this, both in the warp direction and in the weft direction while the thickness is advantageously between 0.30 mm and 3 mm.

The warp and the weft are based on wicks of continuous filaments for technical use, such as in particular glass rovings, the overall titer of which is advantageously between 200 tex and 9600 tex, each consisting of 1 to 8 rovings, having a unit titer between 200 to 4800 tex. These rovings are untwisted and the weight of the fabric is generally between 300 g / m ² and 3000 g / m ² .

The basic fabric is, as indicated above, a fabric produced according to plain or derived armor. Plain armor such as Gros de Towers, fluted, Gros de Naples, plaited or similar, allow to vary easily the width of the strips of son in the warp direction or in the weft direction.

The weakened areas, which will be carried out either on the chain wires or the weft threads, are located on one side of the fabric over the entire width of the wicks, the interval between two weakening zones on a given wire is between 10 and 15 cm. These zones are shifted from wire to wire adjacent.

Thanks to such a design, a structure is obtained which, despite the embrittlement, or even the cutting of a series of its constituents (son of chain or weft threads), however remains homogeneous and easy to handle and allows possibly use it as is.

According to a preferred embodiment, such a fabric is, beforehand .the realization of weakened or cut areas, associated with a fibrous web based on staple fibers such as a glass mat, the connection of the two components being obtained by sewing, knitting, the mesh columns extending parallel between the chain wires, preferably on either side of each wire although it is not imperative.

Possibly, the connection could be obtained by not performing a straight seam, but a real knit of the type with throw, the columns of meshes extending over the face of the fabric whose constituents (warp or weft) must be weakened or cut, and the connecting flanges on the reverse side of the complex formed by the fibrous mat.

In such a case, the weakening or cutting of the wires is preferably made between two columns of mesh to avoid damaging them.

The invention also relates to a method and an installation enabling the production of such a fabric or complex.

• à réaliser un tissu chaíne et trame à partir de mèches sans torsion de filaments continus à usage technique,
• à associer ce tissu éventuellement avec un mat fibreux,

et il se caractérise en ce que on réalise une découpe totale ou partielle des fils de chaíne ou de trame, à intervalles réguliers, sur l'une des faces du tissu, sans détérioration totale du fil de trame ou de chaíne, situé au niveau de la zone de fragilisation en dessous du fil coupé, cette découpe étant réalisée avec un décochement latéral et vertical entre deux fils consécutifs avec un décochement latéral et vertical entre deux fils consécutifs ou groupes de fils juxtaposés travaillant de la même manière dans l'armure du tissu et ce, de telle sorte que deux fils (ou groupes) consécutifs puissent glisser l'un par rapport à l'autre lorsque le matériau est mis en oeuvre.In general, the process according to the invention consists:

• making a warp and weft fabric from twist-free wicks of continuous filaments for technical use,
• to associate this fabric possibly with a fibrous mat,

and it is characterized in that a total or partial cutting of the warp or weft threads is carried out, at regular intervals, on one of the faces of the fabric, without total deterioration of the weft or warp thread, located at the embrittlement zone below the cut thread, this cutting being carried out with a lateral and vertical detachment between two consecutive threads with a lateral and vertical detachment between two consecutive threads or groups of juxtaposed threads working in the same way in the weave of the fabric and this, so that two consecutive son (or groups) can slide relative to each other when the material is used.

• deux cylindres entraínés en synchronisme avec le déplacement du tissu ;
• l'un des cylindres comportant à sa surface une série de lames dont la largeur correspond sensiblement à la largeur des fils (ou groupes) à découper, lesdites lames étant décalées les unes par rapport aux autres, tant latéralement que circonférentiellement selon un dessin reproduisant une armure de type « satin _».

Such a method can be implemented on an installation which also forms part of the invention, installation which is characterized in that it comprises, arranged between a supply station and a reception station, an assembly making it possible to carry out the cutting of warp or weft threads of the fabric, at regular intervals and offset from one thread to the next thread (or group of threads), said assembly comprising:

• two cylinders driven in synchronism with the movement of the fabric;
• one of the cylinders comprising on its surface a series of blades, the width of which corresponds substantially to the width of the wires (or groups) to be cut, said blades being offset with respect to each other, both laterally and circumferentially in a drawing reproducing a "satin _" type weave.

When you want to cut the chain son, these blades will be arranged transversely, whereas in the case where one wishes cut the weft threads, they will be arranged circumferentially.

The second cylinder is a counter-cylinder coated with a layer of rubber or other elastomer, the pressure between the two cylinders being adjustable.

Such an installation makes it possible to control the precision of the action of the knives so that the cutting is carried out only on the chain wire (or weft) of the apparent fabric without deterioration of the weft or the warp thread located in below it.

Brief description of the drawings

• la figure 1 illustre, de manière schématique, la structure d'un tissu conforme à l'invention avant réalisation des zones fragilisées ou découpées ;
• la figure 2 est une représentation graphique schématique d'un tissu réalisé conformément à l'invention ;
• la figure 3 est une vue schématique d'un ensemble d'une installation permettant de réaliser les zones fragilisées et ;
• la figure 4 est une vue schématique en élévation montrant la structure générale de l'ensemble de découpe d'une telle installation.

The invention will however be better understood thanks to the description which follows and which is illustrated by the appended diagrams in which:

• Figure 1 illustrates, schematically, the structure of a fabric according to the invention before making the weakened or cut areas;
• Figure 2 is a schematic graphical representation of a fabric produced in accordance with the invention;
• Figure 3 is a schematic view of an assembly of an installation for making the weakened areas and;
• Figure 4 is a schematic elevational view showing the general structure of the cutting assembly of such an installation.

Way of realizing the invention

Figure 1 schematically illustrates, in perspective, the basic structure of the fabric used in the production of a material according to the invention.

Figure 2 is, for its part, the graphic representation of such a fabric. In such a graph, each square represents the crossing points between the wires of chain (C) and the weft threads (T).

When the warp threads pass over a weft thread, they are identified by the sign (+) and, when they pass under a weft thread, they are identified by the sign (0).

Such a fabric is made in a plain weave or derived from plain, the density in chain (C) and in weft (T) being balanced.

To obtain a product in accordance with the invention, these threads of chain or weft are weakened or cut individually at predetermined intervals. The embrittlement zones are represented in FIG. 2 by the black zones, and are made with a lateral and vertical detachment between two consecutive wires.

Referring to the example illustrated by this figure 2, it can be seen that the armor ratio is four wires (C1, C2, C3, C4) for 12 frames (T1 to T12).

If such a fabric can be used such that, according to one embodiment preferential, it can be combined with a fibrous web based on fibers discontinuous, such as glass mat, the connection of the components being obtained by sewing / knitting, said seams extending parallel between the threads chain, preferably on either side of each wire (C).

Various solutions can be envisaged to realize the zones weakened, the essential point being, during this operation, that the weft thread (or chain) located below the weakened wire is not significantly affected by this operation, and that the consecutive warp (or weft) threads can slide relative to each other during the implementation of the fabric.

Such an operation can be carried out on an installation as illustrated by Figures 3 and 4.

This installation comprises, arranged between a station (1) for unwinding the fabric or complex previously produced and a winding station (2), a set (3) allowing to cut the warp or weft threads of the fabric to regular intervals offset from a wire (C1) relative to the neighboring wire (C2).

In this embodiment, the cutting assembly consists of two cylinders (4,5) rotated at the same speed as the fabric or complex (6). The upper cylinder comprises a series of blades (7) located at its surface, the width of which corresponds substantially to the width of the cut wires, said blades (7) being offset from each other both laterally circumferentially, so as to reproduce the structure of the tissue.

When you want to cut the chain son (C), these blades are arranged transversely as illustrated in Figure 4, while in assuming that we would like to cut the weft threads, they would be arranged circumferentially.

The invention and the advantages which it brings will however be better understood thanks to the concrete examples of implementation given below for information but not limiting.

Example 1

As previously stated, we realize a warp and weft fabric canvas weave.

This fabric is made from wicks of glass threads having a global title, both in the chain and in the weft, of 2400 tex each consisting of 2 rovings elementary of 1200 tex ..

The weaving is carried out so that the warp threads (C) and the threads of weft (T) are, after making the fabric, in the form of flattened ribbons having a width of 9 mm and a thickness of 0.5 mm.

The fabric obtained weighs 500 g / m ² and has no stretch in either the warp direction or the weft direction.

In accordance with the invention, this fabric thus produced is treated on a installation as illustrated in Figures 3 and 4.

In this installation, the cylinder (4) which has a diameter of 30 cm, is a smooth cylinder, coated with a layer of rubber.

The cylinder (5), the diameter of which is also 30 cm, is provided with cutting blades (7) having a width of 10 mm, arranged according to the generators of said cylinder.

The spacing between two consecutive slats in the same row is 108 mm, these blades being offset laterally from one row to the next. These blades protrude 3 mm from the surface of the cylinder.

The lateral offset between these blades is 9 mm and corresponds substantially the width of the wicks (C).

After treatment, in the finished fabric, each warp thread has zones cut, at least partially, spaced apart by a length equivalent to 12 picks, that is to say in this case about 108 mm.

The cutting zones are offset by one wire from the next wire by a value substantially equal to 3 picks.

After completion, such a fabric is practically inextensible in the direction weft, whereas on the other hand, it can be deformed in the warp direction, thanks to the presence of weakened zones which allow displacement of said wires chain relative to each other.

Such a fabric, however, has resistance in the warp direction for allow handling and use.

This product can be used to make shaped laminate materials, such as reinforcement of pipes with variable shapes, beams or profiles of variable section, shaped molded parts obtained by helical winding of the structure of the reinforcement and requiring deformation in one direction, by example when making blades for wind turbines or fans.

Example 2

Example 1 is repeated except that before treatment for weakening the warp threads, the fabric is associated with a glass mat weighing 300 g / m ² .

The whole fabric / non-woven mat is linked by sewing / knitting using threads binding with a title of 16.7 tex.

The seams can be either simple chains or form a knit.

In both cases, the mesh columns preferably extend from one side and other of each warp thread, and are located on the face of the fabric which must be treaty.

The connecting grids between the meshes are, on the other hand, located on the face reverse side of non-woven mat.

Such a complex, after completion, weighs 810 g / m ² and has a thickness of 1.10 mm.

It is particularly suitable to be used for the realization of complexes used for the repair of pipes, as described in the preamble to this application.

Claims (8)

1. A textile material in sheet form, consisting of a warp-and-weft fabric produced from twist-free roving assemblies of continuous technical filaments (glass, carbon, aramid, etc.), characterized in that :

   the fabric is made in a plain weave or derivative thereof, the density of the warp (C) and the weft (T) preferably being balanced;

   the warp yarns (C) or weft yarns (T) are weakened or cut individually at predetermined intervals without any appreciable deterioration in the characteristics of the weft or warp yarns lying beneath the weakening or cutting area; and

   the areas in which a series of yarns, (C) or (T), of the fabric are weakened or cut are produced with a lateral and vertical step between two consecutive yarns.
2. The material as claimed in claim 1, characterized in that the roving assemblies of filaments constituting the warp (C) and the weft (T) are in the form of flattened tapes of large width compared with the thickness.
3. The material as claimed in claim 2, characterized in that the width of the roving assemblies of filaments is between 3 mm and 15 mm, both in the warp direction and in the weft direction, whereas the thickness is advantageously between 0.3 mm and 3 mm.
4. The material as claimed in one of claims 1 to 3, characterized in that the interval between areas of weakening on a given yarn is between 5 and 30 cm, these areas being offset from one yarn to the yarn which is adjacent to it.
5. The material as claimed in one of claims 1 to 4, characterized in that it is combined with a fibrous web based on discontinuous fibers, the two components being bound together by stitching/knitting, the wales extending in a parallel fashion between the warp yarns on either side of each yarn.
6. A process for the production of a material as claimed in one of claims 1 to 5, which consists :

   in producing a warp-and-weft fabric from twist-free roving assemblies of continuous technical filaments,

   in optionally combining this fabric with a fibrous mat,

   characterized in that a complete or partial cut is made in the warp or weft yarns, at regular intervals, on one side of the fabric, without complete deterioration of the weft or warp yarn in the weakening area beneath the cut yarn, this cut being made with a lateral and vertical step between two consecutive yarns.
7. A plant for implementing the process as claimed in claim 6, characterized in that it comprises, placed between a feed station (1) and a take-up station (2), an assembly (3) allowing the warp (C) or weft (T) yarns of the fabric to be cut at regular intervals and in a manner offset from one yarn to the neighboring yarn, said assembly comprising :

   two rolls (4, 5) driven in synchronism with the movement of the fabric ;

   one of the rolls (5) having on its surface a series of blades (7), the width of which corresponds substantially to the width of the yams to be cut, said blades (6) being offset one with respect to another, both laterally and circumferentially in a pattern reproducing a "satin"-type weave.
8. The plant as claimed in claim 7, characterized in that the backup roll (4) is coated with a layer of rubber or elastomer, the pressure between the two rolls (4, 5) being adjustable.

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